[orderlylogic]

I think you would agree, it's useful to understand the Theory of Universal Gravity. For example, you know that if you fall from a high place you will hit the ground..."The proof is in the pudding", so to speak. You probably agree that it is a good idea to have handrails on staircases, correct? Type theory is similarly useful. You can predict what will happen if you enter into a relationship with an ESTP.